Cocytus is also known as the "layer of lamentation", for this is where the winds are the strongest.

Cocytus is the location of a number of godly realms, including the god Erythnul's realm of the Fields of Malice, the bugbear deity Hruggek's realm of Hruggekolohk, Cyric's realm of the Shattered Castle.

Agathion mainly contains holes, which double as portals to other planes. This layer is filled with hidden caches of forbidden knowledge and inhuman creatures. It is notable that Orcus's wand was hidden here when he was slain.